Ingot mold and ingot



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E GATHMANN INGOT MOLD AND INGOT Filed May 23, 1936 2 Sheets-Sheet l Sept. 7, 1937. GATHMANN 2,092,551

INGO'I'*MOLD AND INGOT Filed May 23, 1936 2 Sheets-Sheet 2 Patented Sept. 7, 1937 a UNITED STATES INGOT MOLD AND INGOT Emil Gathmann, Baltimore, Md., assignor to Gathmann Research Incorporated, Catonsville, Md a. corporation of Maryland Application May 23, 1936, Serial No. 81,496

14 Claims.

Thisinvention relates to ingot molds and ingots, and more particularlyto molds and ingots of the general class in which the cross section is corrugated, or comprises inwardly curved and outwardly curved portions.

As is now known in the art, molds having such cross sectional contours possess certain desirable characteristics, one of which is their advantageous effect upon the chilling and cooling oi' the ingot. ,It has been found that the inwardly ex"- tending convex mold wall portions, by projecting inwardly towards the center ofthe ingot and into the mass of ingotmetal, serve to chill the metal quickly, thus resulting in improved crystalline 15 structure of the ingot metal a greater strength in the outer portion or zone 0 the ingot.

I have found that, in order to obtain the most beneficial results, the inwardly extending convex mold wall portions should constitute as large a part'of the entire wall surface as-possible without departing substantially from the smoothly corrugated contour. Thus the contour preferably should include inwardly extending convex wall portions constituting by far the greater part.of

ing concave wall portions should be rounded and struck from radii long enough to prevent the formation of too sharp ribs or .protuberances on the ingot. I have found it advantageous to make the outwardly extending concave wall portions on as small radii as is commensurate with a smoothly corrugated contour. A further important consideration is that of so balancing and apportioning the radii of the convex and the concave wall portions as to provide a contour in which the taper longitudinally from top to bottom of the mold and ingot will be substantially uniform throughout the perimeter and the vertical length of the mold. Contours in accordance with the present invention are particularly ad-, vantageous in molds and ingots in which there is a considerable amount of longitudinal taper.

Accordingly an object of the invention is to provide an ingot mold of corrugated contour in which the inwardly extending convex wall portions constitute by far the greater part of the total wall area and in which the taper from top to bottom is substantially uniform throughout .the perimeter and the vertical length of the mold. A further object is to provide an ingot mold of the kind referred to in which the outwardly extending concave wall surfaces are struck by radii as short as is possible without departing from the smoothly corrugated contour.

A further object is'to provide an ingot having the total wall surface, yet the outwardly extend-- a contour corresponding to the mold contour referred to above. Other objects will'be apparent from a reading of the following description, the appended claims, and the accompanying drawings, in which: 5

Figure 1 is a top plan view of one form of mold embodying the invention;

Figure 2 is a central vertical sectional view of the mold shown in Figure 1;

Figure 3 is a diagrammatic view in of a section on the line 3-4 of Figure trating specific curvatures; V

Figure 4 is a horizontal sectional view of an ingot of the kind produced by casting in a mold as shown in Figures 1 and 2;

Figure 5 is a part plan view of a modified form of mold embodying the invention;

Figure 6 isa part sectional view of an ingot of the kind produced by casting in a mold such as is shown in Figure 5;

Figure 7 is a part plan view of a further modifled .form of mold embodying the invention; and

"Figure 8 is a part sectional view of an ingot of the kind produced by casting in a mold such as that shown in Figure '7. V

The invention may be embodied in molds and ingots of various kinds, such as big-end-up and big-end-down. It will be understood, however, that the invention is not limited to molds and ingots having the specific contours disclosed herein by way of illustrating the invention in its now preferred forms.

Figures 1, 2, and 3 show a big-end-up mold A having a generally round or circular corrugated chamber contour. .The mold is open at the top and is "necked-in at the bottom as shown at I, the necked-in portion being provided with a tapered bottom opening 2. Preferably the longitudinal taper from the necked-in portion upwardly is uniform with the exception of the extreme upper part of the chamber. These features, as described so far, are old in the art and per se do not constitute the invention claimed herein.

In accordance with the present invention, a mold having a generally round cross sectional corrugated contour comprises matrix wall means including a plurality of alternately arranged con-- vex portions which extend inwardly towards the center of the mold chamber, and concave portions which extend outwardly away from the center of the mold chamber. The concave portions are struck by radii which gradually increase in length from one end of the mold to the other and the lines of centers of these radii are inclined with respect to the longitudinal center line of the mold, 55

the nature 10 1 and illusthe radii of the concave portions being quite small at the bottom and smoothly increasing to-, wards the top due to a uniform inclinatioh of thecenter line 6 from the bottom to the top of themold, this inclination being plainly shown by the relative dimensions 6* and 6 in Figure 3 of the drawings. As shown in Figures 1, 2, and 3, the mold chamber is defined by alternately arranged convex wall portions 3 and concave wall portions 4. In order that the chamber willhave the desired longitudinal taper, the lines of centers 5 of the radii R of tho convex wall-portions 3 and the lines of centers 6 of the radii R. ofnthe concave wall portions are inclined with respect to the longitudinal axis or center line 1 of the mold. In this embodiment of the invention the radii R are of equal length from bottom'to'top of the mold, and, in a mold of about nineteen to twenty inches in mean diameter and about sixty inches in height, the radii R preferably may be between three and one-half and four inches in length. j .The radii R. of the concave wall portions 4 gradually increase in length from. bottom to top of the mold and the lines of centers 6 of the radii R are inclined with respect to the axis or longitudinal center line I ofthe mold. In a mold of the size referred to the radii B may vary from about three-eighths inch at the bottom of --the chamber to about one and one-eighth inches at the top. The radii R at the larger end of the mold should not exceedapproximately one-fifteenth of the maximum cross section of ,the mold chamber. The increase in the lengths of the radii contributes to a longitudinal taper but it is not advisable to use radii varying too much, and in order to obtain the desired amount of taper the lines of centers 6 are inclined as shown by the relative dimensions 6' and 6" in Figure 3.

It will be observed that the outwardly extendingconcave wall portions 4 constitute sections of the surfaces of cones whose axes 6 are inclined with respect to the axis 1 of the mold and also with the molds of the mold chamber R.

arrangement and apportioning of the lengths of the radii of thecurved wall portions results in a contour having desired characteristics including: the inwardly extending convex portions eonstituting by far the greater part of the total wall surface and at the same time maintaining. the

smoothly corrugated general contour; and the longitudinal taper being substantially the same throughout the perimeter.

The ingot I shown in Figure 4 has the same general cross sectional contour as the mold shown in Figures 1, 2, and 3, so that no detailed description of the ingot is necessary. Briefly, however,

the ingot contour comprises alternately arranged inwardly extending concave surface portions 3" and outwardly extending convex surface portions 4. Each concave surface portion 3 is of uniform radius from top to bottom and the line of centers of the radii is inclined with respect'to the axis of the ingot. The radii ofeach convex surface 4 vary from top to bottom and the line of centers of the radii of each surface portion 4 is inclined with respect to the axis of the ingot as well as to the surface of the outwardly-projecting s'alients. The radii of the convex surfaces 4 at? the larger end of the ingot should not exceed approximately one-fifteenth of the maximum. cross section of the ingot.

When the mold is small it is preferable for the radii of the inwardly curved convex wall portions to vary from top to bottom of the mold. A mold This relative N of t his kind having a mean diameter of about three :atnd one-half inches and a height of about sixteen. inches is shown in Figure 5. The radii S of the inwardly extending convex wall portions 8 vary from top to bottom. In the mold shown the nadii S vary from two and three-eighths inches at the bottom to one and five-eighths inches at the top. The radii S of the outwardly extenldling concave wall portions 9 vary in length from bottom to top of the mold and the line of centeirs of the radii of each wall portion 9 is inclined with respect to the axis as also with the wall of the mold.

The: ingot J shown in Figure 6 has the same general cross sectional contour as the mold shown in Figure 5. The ingot comprises alternately arranged inwardly-extending concave surface portions 8 and outwardly extending convex surface portions 9'. Each concave surface portion 8' is struck from radii which gradually decrease from bottom to top of the mold, and each convex surface portion 9' is struck from radii which gradually increase in length from bottom to top of the mold, the line of centers for the radii of each convex portion 9' being inclined inwardly with respect to the surface of the ingot.

Figure 7 illustrates the invention as embodied in a rectangular mold O of corrugated contour. Tins mold comprises four inwardly extending convex side wall portions l0, each of which is flanked by outwardly extending concave portions I i which are connected to adjacent primary corner walls l2 by means of inwardly curved secondary corner walls IS. The. primary side walls ID, the primary corner walls 12, and the secondary corner walls l3 all are struck from radii which vary in length from bottom to top of the mold, the line of centers of the radii of each of these wall portions 'preferably being parallel to the axis of the mold; However, in accordance with the present invention, the outwardly extending concave wall portions II are struck from radii T of varying lengths, and the line of centers of the radii of each of the wall portions H are inclined with respect both to the mold axis and the surface of the associated wall portion. In this respect the wall portions II are similar to the wall portions 4 of the mold shown in Figures 1, 3, and 5, see particularly the diagrammatic showing in Figure 3.

The ingot K shown in Figure 8 has a contour correspondinggenerally to that of the mold shown in Figure 7. The ingot contour includes four inwardly extending concave side surface portions l0 each of which is flanked by outwardly extending convex surface portions II which are connected to adjacent primary corner surfaces I2 by means of inwardly curved secondary corner surface portions l3. The radii. of the primary side surfaces III, the primary corners I2, and the secondary corner surfaces l3 vary in length from bottom to top of the ingot, and the lines of centers of these 'radiipreferably are parallel to the axis of the ingot. The radii of the outwardly curved surface portions ll' vary in length from bottom to top of the ingot, and the lines of centers of these radii. are inclined with respect to both the axis and surface of the ingot.

By using contours of the kind described above it is possible to have the outwardly extending concave mold wallv portions struck on as small radii as is compatible with the maintaining of a smoothly corrugated contour, and smaller than has heretofore been possible with radii of uniform length or with radii struck from centers parall' lrwithztheaaxes oftthef causes -the i w r ,1 i

, neiu ttmath ma ically nilallr f0. perimeter -S ru tu esihavine ntau. m ni ve i t rret-eds ZSUQ a h (in l tie: ang im.

The specific contour of any mold may have to be varied in dependence upon such factors as mold size, ingot metal analysis, and melting and pouring practice, so that various changes may be made in the contours disclosed herein for illustrative purposes without departing from the in vention as defined in the claims.

I claim:

1. A longitudinally tapered ingot mold having inwardly extending convex wall'portions and outwardly extending concave wall portions, said concave wall portions comprising surfaces of cones having their axes inclined with respect to the longitudinal center line of the mold chamber, said axes sloping away from said center line from the smaller end of the mold to the larger "end thereof.

2. A longitudinally tapered ingot mold having inwardly extending convex wall portions and outwardly extending concave wall portions, at least some of said portions being generated by radii which gradually increase in length from the smaller end of the mold to the larger end thereof and the lines of. centers of which are inclined with respect to the longitudinal center line of the mold chamber, said lines of centers sloping away from the center line of the mold from the smaller end of the mold to the larger end thereof.

3. A longitudinally tapered ingot mold having inwardly extending convex wall portions and outwardly extending concave wall portions, at least some of said concave portions being generated by radii which gradually increase in length from the smaller end of the mold to the larger end thereof and the lines of centers of which are inclined with respect to the longitudinal center line of the mold chamber, said lines of centers. sloping away from the center line of the mold from the smaller end of the mold to the larger endthereof.

4. A longitudinally'tapered ingot mold having inwardly extending convex wall portions and outwardly extending concave wall portions, at least some of said convex portions being generated by radii which gradually increase in length from the smaller end of the mold to the larger end thereof and the lines of centers of which are inclined with respect to the longitudinal center line of the mold chamber, said lines of centers sloping away from the center line of the mold from the smaller end of the mold to the larger end thereof.

'extien'ding 'conyexgwallaportions and out {extending c concavez-siswalh e'portion's; 'said .jconvexrwaill portions poinprisingsurfacestof: cones havingotheimgaxes iinclinedoiwithlirespect to 'the longitudinal reenter: linl ffoflith i'mol saidraxesirslopingt from {the smalle surface portions and prising four side walls and four corner walls' apered' lingotz h'aving outdefining a chamber generally rectangular in cross sectionf'at leasttwo opposed side walls each comprising a centrally disposed primary side wall portion, two outwardly extending concave wall portions flanking and merging with the primary side wall portion, and two secondary corner wall portions flanking and merging with said concave wall portions and connecting the latter to the adjacent corner walls, said concave wall portions being generated by radii which gradually increase in length from the smaller end of the -mold to the larger end thereof and the lines of centers of which are inclined with respect to the longitudinal center line of the mold cham-- her, said lines of centers sloping away from the center line of the mold from the smaller end of the mold to the larger end thereof.

10. A longitudinally tapered ingot generally rectangular in cross section and comprising four surfaces each comprising a cento the longitudinal center line of the ingot, said lines of centers sloping away from the center line of the ingot from the smaller end of the ingot to the larger end thereof.

11. A tapered ingot mold having inwardlyextending convex wall portions and outwardlyextending concave wall portions, at least some of said concave portions being generated by radii the larger end thereof,

which gradually increase in length "from one end of the mold" to the other and the lines of centers of which are inclined with respect to the longitudinal center of the mold chamber, said line's-oi centers sloping-away from the center line of the mold from the smaller end of the mold to end of the mold not exceeding approximately one-fifteenth of the maximum cross section of said mold chamber.

12. A tapered ingot having outwardly-extending convex surface portions and inwardly-extending concave surface portions, at least some of said convex portions being generated by radii which gradually increase in length from one end of the ingot to the other and the lines of centers of which are inclined with respect to the longitudinal center line of the'ingot, said lines of. centers sloping away from the center line of the ingot from thesmaller end of the ingot to the larger end thereof, said radii at the larger end-of the ingot not exceeding approximately one-fifteenth of the maximum cross section of said ingot.

said radii at the larger Y 13. A longitudinally tapered ingot mold comprising side walls and concave comer walls de fining its chamber, saidcorner walls being generated by radii which gradually increase in length from the smaller end of the-mold to the larger end thereof and the lines of centers of which are inclined with respect to the longitudinal center line of the mold chamber, said lines of centers sloping away from the center line of the mold from the smaller end ofv the mold to the larger end thereof.

14. A longitudinally tapered ingot comprising side surfaces and convex corner surfaces, said corner surfaces being generated by radii which gradually increase in length from the smaller end of the ingot body to the larger end thereof and the lines of centers of which are inclined with respect to the longitudinal center line of the ingot, said lines of centers sloping away from the center lineof the ingot from the smaller end of the ingot body to the larger end thereof.

EMIL GATHMANN. 

